A study published in JAMA Internal Medicine in December 2014 looked at decision fatigue in primary care providers. The researchers focused on antibiotic prescriptions for acute respiratory infections (including those for which antibiotics are never indicated) over a 16-month period covering 21,867 visits to 204 clinicians. They compared the rate of antibiotic prescription at the first, second, third, and fourth hour of clinic, with the premise being that over a period of repeated decision making the quality of the decisions declines ( JAMA Intern. Med. 2014;174:2029-31 ).

If, like me, you think you have unrealistic expectations about physicians being unimpeachable, you might be disappointed to learn that antibiotic prescriptions were significantly higher for the third and fourth hour of clinic. It seems that as the clinic session wore on, physicians opted for the “safer,” “easier” option.

Another paper involving similarly weighty consequences was published in 2011 in Proceedings of the National Academy of Sciences (and cited as one of only six references in the JAMA paper). The researchers looked at parole decisions made by judges in four Israeli prisons. Data from 1,112 judicial rulings involving eight judges showed that “the percentage of favorable rulings drops gradually from ~65% to nearly zero within each decision session and returns abruptly to ~65% after a break” ( Proc. Natl. Acad. Sci. U.S.A. 2011;108:6889-92 ). (Breaks lasted about 30 minutes and involved a meal.) That’s a pretty dramatic rate of change. It is sobering to think of lives being hugely affected by such seemingly irrelevant details. Talk about fate being fickle.

Decision fatigue suggests that when we make repeated decisions over a brief period of time there is an erosion of self-control and we are more likely to choose the “affectively pleasing” option. It has been written about in psychology journals for the past 2 decades, but for practical and ethical reasons, most studies on the subject involve minor decisions, such as what to choose at the grocery store or which items to add to one’s wedding registry. The concept has become quite popular in the fields of behavioral economic and advertising. It is the reason groceries display candy at the cash register.

Decision fatigue is part of a larger theory on our executive functions, proposed by Dr. Roy Baumeister, professor of social psychology at the University of Florida. His central idea is that self-control, volitional acts, responsibility, and self-regulatory efforts “draw upon a common resource and deplete it.” He calls it ego depletion. In one simple but powerful experiment, researchers conducted a study where students were asked to commit either two digits or seven digits to memory. When offered a choice of fruit salad or chocolate cake as compensation for participation in the study, those who had to remember seven digits were far more likely to choose the chocolate cake – certainly the more “affectively pleasing” option. So ego depletion is to blame for my constant kitchen-grazing behavior at the end of a trying clinic day. Apart from affecting my waistline, I’m sure it affects me in ways that I am unaware of, ways that may have an impact not just on patients but on society, too.

The JAMA Internal Medicine article seems to be the first of its kind in the medical literature. To me, it is hugely important because it reminds us of two major truths: that there are often bigger things at stake, and that doctors, being mere mortals, are not exempt from human frailty.

Dr. Chan practices rheumatology in Pawtucket, R.I.